Linear basic polymers, their preparation and their use
AssigneeBASF SE
InventorsFritz Brunnmueller, Rolf Schneider, Michael Kroener, Hans Mueller, Friedrich Linhart
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Abstract
Linear basic polymers containing, as characteristic components, from 90 to 10 mole % of copolymerized units of the formula ##STR1## and from 10 to 90 mole % of copolymerized units of the formula ##STR2## are obtained by polymerizing the compound of the formula CH.sub.2 .dbd.CH--NH--CHO (N-vinylformamide) to a polyvinylformamide in the presence of a free radical polymerization initiator and splitting off the formyl group from the resulting polymer at from 20.degree. to 200.degree. in the presence of an acid or base. The reaction products are used as retention agents, drainage assistants and flocculants in papermaking.
Claims8
A linear basic polymer containing from 90 to 10 mole % of units of the formula ##STR9## and from 10 to 90 mole % of units of the formula ##STR10## and having a Fikentscher K value of from 10 to 200 (measured in 0.5% strength aqueous sodium chloride solution at 25.degree. C.).
In a process for papermaking, the improvement comprising adding from 0.005 to 0.5% by weight, based on the dry fiber, of a linear basic polymer containing 90 to 10 mole % of units of the formula ##STR11## and from 10 to 90 mole % of units of the formula ##STR12## and having a Fikentscher K value of from 10 to 200 (measured in 0.5% strength aqueous sodium chloride solution at 25.degree. C.) to stock before sheet formation.
Dependencies are inferred from the claim text.